Cellular structure

ABSTRACT

A cellular structure such as a honeycomb window treatment comprises a plurality of rows of elongated cells secured to one another. Each of the rows is constructed by providing a first longitudinally extending length of material, which includes a first surface and a second surface, as well as, a lesser width portion and a greater width portion. A second length of material is also provided that includes a first surface and a second surface of the first material. The second surface of the second material is secured to the first surface over the greater width portion of the first material along a plurality longitudinally extending locations on the second surface of the second material to form a row. A longitudinally extending crease is also formed in the first material such that the lesser width portion and the greater width portion of the first material lie on opposite sides of the crease.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of application Ser. No. 11/484,397,filed Jul. 11, 2006, which is a continuation of application Ser. No.11/166,453, filed Jun. 24, 2005, now issued as U.S. Pat. No. 7,074,475,which is a divisional of application Ser. No. 10/281,561, filed Oct. 28,2002, now issued as U.S. Pat. No. 6,989,066, both by Fu-Lai Yu, whichare hereby incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to an expandable cellular structure suchas used in honeycomb window shades, having a plurality of parallelelongated cells.

BACKGROUND OF THE INVENTION

Expandable cellular structures that are often used as honeycomb windowshades consisting of a plurality of elongated tubular cells are wellknown in the art. Honeycomb window shades provide consumers withnumerous advantages in window coverings such as improved insulation,light filtering, and aesthetic appeal. The present invention relates tocellular structures and a method for making the cellular structures thatutilizes a novel system of cutting, folding, gluing and arranging stripsof fabric material in the construction of honeycomb panels.

The cells within such cellular honeycomb structures are constructed of aflexible material with each cell extending across the width of thestructure and in a parallel relationship to the other cells. The volumeoccupied by each cell is decreased or expanded, respectively, bycollapsing the cells together or spreading them apart. The expandableattributes of the cells provides a useful structure for covering areasof various sizes.

Many of the current cellular structures have pleats extending along thelength of each cell. The pleats are generated by placing creases in thematerial during cell fabrication. The pleats assist in the orderlycollapsing of individual cells as the structure is compressed. Thepleats also result in the face and back of the structure having acorrugated appearance which is similar to that of an accordion.

One shortcoming experienced with standard honeycomb shade constructionsthat results in an undesired aesthetic appearance is due to the wayhoneycomb shades achieve their shape. Typically, honeycomb blinds arecomprised of creased and folded lengths of material. The folded lengthsof materials have a spring coefficient that prevents the folded materialfrom completely stretching out, and thereby maintaining the pleated orhoneycombed appearance.

Because the structure of the honeycomb structure is based on the springcoefficient of the material, however, the overall appearance of aconventional honeycomb panel is affected by the varying amount of weightsupported by any particular cell of the honeycomb panel. Cells of thehoneycomb panel that are located towards the top of the shade mustsupport the weight of all the material below it and are stretched muchmore than cells located towards the bottom of the shade, which have lessweight to support. As such, the predominance of the pleats emanatingfrom those cells towards the top of the structure will graduallydiminish as the amount of weight being supported by each cell increases.Thus, the cellular structure will fail to provide a uniformlydistributed pleated appearance. The top cells will appear almost flatwhile the bottom cells will remain substantially pleated. The result ofthis is an uneven appearance and uneven shading ability of the blind.Over time, the cells towards the top of a shade may also be stretchedsuch that the material loses its ability to retain a creased or pleatedappearance.

The inability of a typical honeycomb cellular structure to limit theextent particular cells may be stretched also results in a waste ofmaterial. This is because with conventional honeycomb constructions abalance must be achieved with the cellular structure such that cellstowards the top of the shade are not overly distorted while stillallowing cells towards the bottom of the shade to extend sufficiently toprovide a desirable aesthetic appearance. Often, a compromise is madesuch that honeycomb cells towards the bottom of a shade are not fullyextended by a heavier weight to prevent cells at the top of the shadefrom being too stretched out. As a result, more cells will be needed tocover a window space than would be necessary if cells at the bottom ofthe shade could be fully extended. As a result, the material costs ofproviding additional rows of honeycomb cells than would otherwise benecessary to cover a window are increased.

Another shortcoming presented by most cellular honeycomb window shadesis due to the fact that they are made with a single type of material isused throughout the window shade. This lack of flexibility in theability to choose from different fabrics to provide different coloring,shading, and insulation combinations is simply not possible with shadesconstructed from a single type of material.

Accordingly, what is needed is a cellular structure as used in ahoneycomb window shade that preferably maintains its pleated appearancefrom top to bottom when it is fully extended. The cellular structure ofthe window shade should be designed such that the cells collapserepeatably the same way to provide for a uniform and desirableappearance. What is further desired is a method of making a cellularhoneycomb structure, wherein the shade constructed limits the amount anyparticular cell may be stretched and enables all the cells to be fullyextended and provide a uniform appearance without the shortcomings oftypical honeycomb blind structures. What is further desired is a windowshade that offers the flexibility to choose different combinations oftypes of material for the shade. The present invention meets thesedesires.

SUMMARY OF THE INVENTION

The present invention relates to a cellular structure such as used inhoneycomb window shades having a uniformly pleated outer surface on itsface and back, and a method for making the cellular structure. Thestructure has an aesthetically pleasing pleated appearance which is notlost over an extended period of time. Each cell along the outer visiblesurface of the structure will preferably have a uniform shape and sizewhen the shade is fully extended.

A cellular structure is constructed by securing a plurality of rowscomprising elongated cells to one another. In a preferred form of theinvention discussed in further detail below, each row forms one cell,and then cooperates with adjacent rows to define other cells. Each ofthe plurality of rows is constructed by providing a first longitudinallyextending length of material. This first material includes a firstsurface and a second surface. The first material also defines a lesserwidth portion and a greater width portion. A longitudinally extendingfold or crease is formed in the first material such that the crease islocated between the lesser width portion and the greater width portion.

A second longitudinally extending length of flat material is alsoprovided for each row. The second material has a first surface and asecond surface. The second material is secured via its second surface tothe first surface of the first material by along at least onelongitudinal location. Preferably, the second material also comprises afirst minor width and a first major width. To form one of the pluralityof rows of the cellular structure, the second surface of the secondmaterial is preferably secured to the first surface of the firstmaterial on the greater width portion along a plurality oflongitudinally extending locations on the second surface of the secondmaterial. These longitudinally extending locations are preferablydefined by glue or adhesive lines.

In a preferred embodiment, the lesser width portion of the firstmaterial is preferably greater than one-quarter of the total width ofthe first material. The greater width portion further comprises a secondminor width and a second major width. The greater width portion is madeup of the remainder of the first material. A fold or crease is formedbetween the lesser width portion and greater width portion. The lesserwidth portion of the first material is folded over the first surface ofthe first material on the greater width portion. In one embodiment, thisfolding process causes the lesser width portion to lie essentially ontop of and parallel to the greater width portion. Alternatively, sincethe lesser width portion will not be adhered to the greater widthportion, the lesser width portion may alternatively be folded such thatan angle is formed between the lesser width portion and greater widthportion that is less than 90 degrees, and does not lie on top of thegreater width portion.

The second length of material is preferably secured to the firstmaterial to form a row such that an outer edge of the greater widthportion of the first material and an outer edge of the second materialare coterminous. In other words, the outer edge of the greater widthportion of the first material and the outer edge of the second materialpreferable form an even edge for the row. The second material ispreferably secured to the first material by two glue lines positioned atopposite edges of the second material after the first material has beenfolded. Alternatively, the second material may be secured to the firstmaterial prior to or at substantially the same time as the creasing andfolding of the first material.

Each row is stacked with other rows, and each of the plurality of rowsis secured to one or more adjacent rows. If a row is to be the top orbottom row of a shade, then it will only be secured to one adjacent row,and will be secured to either a head rail or a bottom rail. Otherwise,each row will have two adjacent rows to which it must be secured. Rowsare secured such that the lesser width portion of the first material andthe second material of one row is secured to the second surface of thegreater width portion of the first material of an adjacent row.

To secure two rows together, it is preferred that two glue lines aresandwiched between the completed rows. One glue line secures the secondside of the first material on an edge of the lesser width portion to thesecond side of the first material of an adjacent row. A second glue linealso secures the first surface of the second material to the second sideof the first material of an adjacent row. This second glue line ispreferably placed between the first minor width and the first majorwidth.

In a preferred form of the present invention, the first major width isgreater than the first minor width. The first major width will face theoutside or visible portion of the shade, such as the face or back of theshade, whereas the first minor width will be in the interior of thecellular structure and not noticeably visible once the shade iscompleted. As explained further below, the first major width will formpart of the visible portion of the shade having a pleated appearance.

Although the way pieces of material and rows are secured togetherdiscussed thus far has been glue lines, the manner of securing thedifferent fabric materials and completed rows together may beaccomplished by any appropriate means. Examples of such techniques knownin the art include bonding with glue or adhesive, ultrasonic welding,and knitting.

Once joined, the completed rows cooperate to define avertically-collapsible double honeycomb fabric structure wherein eachrow has two alternatingly staggered columns of cells. The amount thehoneycomb shade may be stretched or extended during normal use islimited such that when fully extended, the cells towards the top of theshade will have substantially the same configuration as the cellstowards the bottom of the shade to provide even shading and anaesthetically enhanced appearance. The way in which each cell of thecellular structure may be limited as to how much it can be stretchedwhen the window shade is opened is now discussed in further detail.

The cellular structure may be limited by a combination of twocooperating parts. The first part is the first minor width. The firstminor width is the portion of the second material that, when thecellular structure is completed, will form part of the interior wall ofthe cells. The width of this first minor width is less than half thetotal width of the second material. The remainder of the second materialis the first major width. Preferably, the location along the secondmaterial at which the second material is secured to an adjacent row isat the intersection of the first major width and the first minor width.

The second part of the limiting combination of parts is the second minorwidth portion of the first material. Preferably, the second minor widthis the portion of the greater width portion of the first materialextending from the position at which the first material is secured tothe inner edge of the second material to the position at which thesecond surface of the first material is secured to an adjacent row. Thesecond minor width is preferably the same width as the first minorwidth, and cooperates with the first minor width to complete an interiorcell wall. The portion of the first material between the position atwhich the second surface of the first material is secured to an adjacentrow to the outer edge of the first material is the second major portion.

This first combination of parts, the limiting combination that limitsthe amount cells can be extended, is made up of the first minor widthand the second minor width. The width of this first combination isshorter than a second combination, which is made up of a first majorwidth and the second major width. As such, when the cells are extended,the first combination of any particular row will reach the limit towhich the row may be stretched and the aggregate of first combinationswill act to limit the extension of the overall cellular structure.Meanwhile, the second combination of each row remains flexed, therebymaintaining a pleated appearance. In other words, when the firstcombination is fully extended the first minor width and second minorwidth will form a substantially coplanar structure. Since the secondcombination is longer than the first combination, the second combinationwill not be fully stretched, and thereby, form an angle and maintain apleated appearance.

It is contemplated that, if desired, the second material may be adifferent material from the first material. For example, the secondmaterial may be of a different color, or may have different lighttransmission properties.

Other features and advantages of the present invention will becomereadily apparent from the following detailed description, the appendeddrawings, and the accompanying claims.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

FIG. 1 is a foreshortened cross sectional schematic view of a fullyopened embodiment of a honeycomb panel constructed according to thepresent method;

FIG. 1 a is a closeup view of two rows of the cross sectional schematicof FIG. 1.

FIG. 2 is a cross sectional schematic view of first and a secondlongitudinally extending lengths of material;

FIG. 3 is a cross sectional schematic view of a completed row;

FIG. 4 is a cross sectional schematic view of a stack of completed rows;

FIG. 5 is a cross sectional schematic view of an alternative embodimentof first and a second longitudinally extending lengths of material;

FIG. 6 is a cross sectional schematic view of a completed rowconstructed according to the alternative embodiment;

FIG. 7 a is a cross sectional schematic view of an alternativeembodiment of first and a second longitudinally extending lengths ofmaterial;

FIG. 7 b is a cross sectional schematic view of an alternativeembodiment of a completed row;

FIG. 7 c is a cross sectional schematic view of an alternativeembodiment of a stack of completed rows; and

FIG. 7 d is a foreshortened cross sectional schematic view of analternative embodiment of an opened embodiment of a honeycomb panelconstructed according to the alternative method.

DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

The invention disclosed herein is, of course, susceptible of beingembodied or conducted in many different manners. Shown in the drawingsand described herein below in detail are preferred embodiments of theinvention. It is to be understood, however, that the present disclosureis an exemplification of the principles of the invention and does notlimit the invention to the illustrated embodiments. Moreover, it isunderstood that the figures herein do not necessarily show details ofthe cellular structure made according to the present invention that areknown in the art and that will be recognized by those skilled in the artas such. The detailed descriptions of such steps or elements such as thestructure of the apparatus for cutting the shade material, theattachment of head rails and bottom rails, the curing process foradhesives that may be used, or the stacking apparatus are not necessaryto an understanding of the invention. Accordingly, such steps orelements are not depicted herein.

Referring to FIG. 1 and FIG. 1 a, in accordance with a preferredembodiment of the present invention, a cross sectional view of a fullystretched or extended window shade 10 having a honeycomb cellularstructure is shown. As shown, the window shade 10 is comprised ofseveral rows, each row including a number of components. One componentis a first material 20, which is a longitudinally extending length ofmaterial. The first material has a first surface 30 and a second surface40. Another part forming the window shade 10 is a second material 50,which is also a longitudinally extending length of material. The secondmaterial also has a first surface 60 and a second surface 70.Preferably, in construction, second material 50 is the same type ofmaterial as first material 20. It is possible however, to utilize adifferent type or color of material for first and second materials 20,50 to create different textures, qualities, transparency, or appearancesfor the overall window shade 10.

Second material 50 is secured to first material 20 along longitudinallyextending areas, preferably by glue lines 80, 90. When second material50 is secured to first material 20 a row is formed defining one completecell 130, and approximately one-half of another cell 120.

Rows, such as rows 240 and 250 as shown in FIG. 4, are stacked andadjacent rows secured to one another to create the desired number ofrows for window shade 10. As shown, rows are secured to the stack 220 atlongitudinally extending areas, preferably by glue lines. For examplerow 250 is added to stack 220 and secured by glue lines 100, 110. Asshown in FIGS. 1 and 4, the plurality of rows that are secured together,such as rows 240 and 250, cooperate to complete a cell of an adjacentrow. For example, as shown in FIG. 1, the first material 20′ of anadjacent row, cooperates with first material 20 and second material 50to form cell 120.

The rows, when fully extended, define a vertically-collapsible doublehoneycomb cellular structure having two staggered columns of cells. Theamount any particular cell of the cellular structure may be stretched orextended during normal use is limited such that when fully extended, thecells towards the top of the shade will have substantially the sameconfiguration as the cells towards the bottom of the shade to provideeven shading and enhanced aesthetic appeal. For example, as discussed infurther detail below, cell 130 is limited as to how much it can beextended by the limiting combination made from a portion of the firstmaterial 20 and a portion of second material 50.

Cell 130 is limited as to how much it can be extended by a first orlimiting combination of first minor width 55 of the second material 50and second minor width 25 of the first material 20. As shown in FIG. 1a, the first minor width 55 is the distance along second material 50from an inner edge 52 to glue line 110′. First minor width 55 has awidth that is less than half the total width of second material 50. Thesecond minor width 25 is the distance along first material 20 from glueline 80 to glue line 110. The second minor width 25 is preferably thesame width as the first minor width 55. This first or limitingcombination will be shorter than a second combination, which is made upof a first major width 57 and the second major width 27. The first majorwidth 57 is shown as the distance along second material 50 from theouter edge 190 of the second material 50 to glue line 110′. The secondmajor width 27 is shown as the distance along the first material 20 fromthe outer edge 200 of the first material 20 to glue line 110. The firstcombination, which is shorter than the second combination, will act tolimit the extension of cell 130. When the first combination is fullyextended the first minor width 55 and second minor width 25 will form asubstantially coplanar structure. Since the second combination is longerthan the first combination, the second combination will not be fullystretched and first major width 57 and second major width 27 will formand angle and maintain a pleated appearance.

The extent to which cell 120 may be stretched is similarly limited. Cell120 is limited by the combination of first minor width 55 and a secondminor width 25′ of an adjacent row. The outer portion of cell 120 isshown as being made up of a portion of the first material 20. Thisincludes the lesser width portion 170 and a corresponding width ofgreater width portion 180. Preferably, lesser width portion 170 will beof substantially equal width to the first major width 57 of the secondmaterial 50 and the second major width 27 of the first material 20. Assuch, the outer portion of cell 120 will not be fully extended whenfirst minor width 55 and second minor width 57′ are extended, andmaintain a pleated appearance.

Referring now to FIGS. 2 through 4, one preferred method of making thehoneycomb window blind 10 is explained. As shown in FIG. 2, a firstmaterial 20 having a first surface 30 and a second surface 40 is creasedand folded. Crease 160 is made between lesser width portion 170 andgreater width portion 180 of first material 20. Lesser width portion 170is folded over greater width portion 180 such that lesser width portion170 lies on and partially over the first surface 30 of greater widthportion 180. Preferably, crease 160 is made such that the lesser widthportion 170 is greater than one-quarter the total width of firstmaterial 20. Alternatively, one can first adhere second material 50 tofirst material 20 and then fold first material 20.

A second material 50 is also provided as shown in FIG. 2. Secondmaterial 50 is preferably of a width that is less than one-half thetotal width of first material 20. In this embodiment of the presentmethod, second material 50 is not creased or folded prior to assembly ofthe window shade 10. As shown in FIG. 3, it is preferred that a pair ofglue lines 80 and 90 are applied to the first surface 30 of firstmaterial 20 before securing second material 50 to first material 20, andare located such that the outer edge 190 of second material 50 issecured at or near the outer edge 200 of first material 20, and suchthat the second surface 70 of second material 50 is secured to the firstsurface 30 of first material 20 at the inner edge 52 of the secondmaterial 50. It is most preferred that outer edge 200 of first material20 and outer edge 190 of second material 50 are coterminous such thatthe outer edge 200 of first material 20 and outer edge 190 of secondmaterial are even.

After a row is completed as shown in FIG. 3, it is stacked with andsecured to other completed rows such as shown in FIG. 4. Prior to a rowbeing added to a stack 220, such as row 250, glue lines 100 and 110 arepreferably applied to stack 220. These glue lines are preferably placedas shown in FIGS. 3 and 4. For example, a first glue line 100 is appliedlongitudinally on the second surface 40 of the first material 20 on thelesser width portion 170. A second glue line 110 is appliedlongitudinally to the first surface 60 of the second material 50. Asdiscussed, the glue line 110′ defines first major width 57 and firstminor width 55 of the second material 50. Glue line 110 similarlydefines second major width 27 and second minor width 25 of the firstmaterial 20.

As a row, such as row 240 shown in FIG. 4, is added to the stack 220,the row is adhered to the stack by way of the second surface 40′ of thefirst material 20′ by glue lines 100′ and 110′. Glue line 100′ is alsopreferably located near an edge 230 of the lesser width portion 170.After the desired number of rows are added, the stack 220 is taken to acuring station (not shown) to permanently join together the first andsecond materials, 20, 50 for each of the completed rows, as well as topermanently join the rows.

As an alternative method for constructing a window shade 10 withhoneycomb structure, reference is made to FIGS. 5 and 6. In thisembodiment, a first material 320 having a first surface 330 and a secondsurface 340 is creased and folded. Similar to the previous embodiment,crease 460 is made between a lesser width portion 470 and a greaterwidth portion 480 of first material 320. Lesser width portion 470 isfolded over greater width portion 480 such that an angle is formedbetween lesser width portion 470 and greater width portion 480 that isless than 90 degrees. Crease 460 is located between lesser width portion470 and greater width portion 480 such that the lesser width portion 470is more than one-quarter the total width of first material 320. A secondcrease 500 is also formed in the first material 320. Preferably, thedistance from crease 500 to the outer edge 510 of first material 320 isequal to the lesser width portion 470 of first material 320.

A second material 350 is also provided. Second material 350 ispreferably of a width that is less than one-half the total width offirst material 320. In this embodiment of the present method, secondmaterial 350 is folded to form crease 360 prior securing second material350 to first material 320. Crease 360 is preferably formed between afirst major width 357 and a first minor width 355 of the second material350. It is preferred that prior to securing second material 350 withfirst material 320, that a pair of glue lines 380 and 390 are applied tothe first surface 330 of first material 320, which are located such thatthe outer edge 490 of second material 350 is secured at or near theouter edge 510 of first material 320, and such that the inner edge 495of second material 350 is secured to the first surface 330 of firstmaterial 320. Preferably, the outer edge 490 of second material 350 iscoterminous with the outer edge 510 of the first material 320.

The stacking of the completed row according to this second embodiment isessentially the same as described with the first embodiment. After thedesired number of rows have been stacked, the adhesive may be cured andthe appropriate bottom rail and head rails attached. The extent to whichthe completed structure may be stretched in this embodiment is limitedessentially in the same manner as discussed above.

As yet another method of assembling the described honeycomb structure,one may take first material 20 and form a crease in first material 20 asdescribed. First material 20 can then be stacked. A second material 50can then be secured to first material 20 while first material 20 is inthe stack as described above. Another first material 20 can then besecured to the top of the stack. Another second material 50 can then besecured to the stack. In other words, instead of completing a row andthen stacking additional completed rows, stacking the pieces of materialthat make up the rows is done while the rows are being constructed.

Shown in FIGS. 7 a-7 d is another embodiment of the claimed invention.As shown in FIG. 7 a, a first material 600 having a first surface 610and a second surface 620 is provided. A second material 630 having afirst surface 640 and second surface 650 is also provided. As shown inFIG. 7 b, the first material 600 and the second material 630 are bondedtogether with glue line 660. As shown in FIG. 7 c, similarly formed rowsare stacked and secured together to form the cellular honeycombstructure 710. For example, row 670 is secured to row 680 via glue lines690 and 700. FIG. 7 d shows the cellular structure 710 in an expandedform.

1. A double cell structure for a window covering having a rear and aface, the window covering comprising: a vertical first column of cells,each of the cells of the first column including a first visible sectionand a concealed section when viewed from the face; a vertical secondcolumn of cells, the second column of cells being adjacent to andconnected with the first column of cells, each of the cells of thesecond column defining a second visible section and the concealedsection when viewed from the rear, the adjacent cells of the firstcolumn and the second column defining a plurality of rows; and at leastone of the rows including: a first material and a second material,wherein the first material is attached to the second material; the firstmaterial defining the first visible section, a portion of the concealedsection, and a portion of the second visible section; the secondmaterial defining a portion of the concealed section and a portion ofthe second visible section; and a first material of an adjacent rowdefining a portion of the concealed section.
 2. The double cellstructure of claim 1, wherein the first visible section includes a pleatand the second visible section includes a portion defined by an edgeportion of the first material attached to an edge portion of the secondmaterial.
 3. The double cell structure of claim 2, wherein the edgeportion of the first material is co-terminus with the edge portion ofthe second material.
 4. The double cell structure of claim 1, whereinthe concealed section is shorter than a combination of the first visiblesection and the second visible section.
 5. The double cell structure ofclaim 1, wherein the cells of the first column are staggered withrespect to the cells of the second column.
 6. The double cell structureof claim 1, wherein the cells of the first column of cells are ofsubstantially the same size as the cells of the second column of cells.7. A double cell panel for a window covering having a face and a rear,the panel comprising: a plurality of rows; at least one of the rowsincluding a front cell and a rear cell; the rear cell including avisible section when viewed from the rear comprising a first materialand a second material, the rear cell further including a first concealedsection comprising the first material and the second material, the firstconcealed section being shorter than the visible section; and the frontcell including a visible section comprising the first material, thefront cell further including a second concealed section comprising thesecond material and the first material of an adjacent row, the visiblesection of the front cell being longer than the second concealedsection.
 8. The double cell panel of claim 7, wherein the visiblesection of the front cell includes a pleat and the visible section ofthe rear cell includes a portion defined by an edge portion of the firstmaterial attached to an edge portion of the second material.
 9. Thedouble cell panel of claim 8, wherein the edge portion of the firstmaterial is co-terminus with the edge portion of the second material.10. The double cell panel of claim 7, wherein the first concealedsection is shorter than the visible section of the front cell.
 11. Thedouble cell panel of claim 7, wherein the front cell is verticallyoffset relative to the rear cell.
 12. The double cell panel of claim 7,wherein the front cell is substantially the same size as the rear cell.13. A cellular structure comprising: a first series of cells and asecond series of cells, alternating cells of the first series of cellsand the second series of cells being oppositely oriented, the secondseries of cells being offset relative to the first series of cells, andalternating cells of the first and second series defining a plurality ofrows; each of the plurality of rows including a limiting member; each ofthe first series of cells comprising a first outwardly extending outerportion comprising a first portion of a first material; each of thesecond series of cells comprising a second outwardly extending outerportion comprising a second portion of the first material and a firstportion of a second material; and each limiting member comprising athird portion of the first material, a second portion of the secondmaterial, and a portion of a first material of an adjacent row.
 14. Thecellular structure of claim 13, wherein the first outwardly extendingouter portion includes a pleat and the second outwardly extending outerportion includes an edge portion of the first material attached to anedge portion of the second material.
 15. The cellular structure of claim13, wherein the edge portion of the first material is co-terminus withthe edge portion of the second material.